Head support device, disk device having the head support device, and portable electronic device having the disk device

A head support device comprising:

• a head slider having a signal transducer;
• a head support arm having first end coupled to the head slider;
• a voice coil coupled to a second end opposite to the first end of the head support arm with respect to a horizontal rotary shaft, which rotates the head support arm in parallel with a recording disk surface;
• a pair of pivots forming a vertical pivot axis about which the head support arm pivots vertically with respect to the disk surface;
• and
• an elastic mechanism for generating load which urges the head slider toward the disk surface about the vertical pivot axis as a center,
• wherein a gravity center position of a total mass of members, other than the head slider, that pivot about the vertical pivot axis substantially agrees with a position of the vertical pivot axis,
• wherein gravity center position δ is placed in a region defined as and formed of the head support arm as a coordinate axis, the vertical pivot axis as an origin, the head slider side as a positive region, and the other side of the head slider side as a negative region,
• wherein a moving amount of the head slider upon receiving an allowable maximum impact acceleration along a direction perpendicular with respect to the disk for pivoting the head support arm to approach the disk is δ1+ upon the gravity center position δ of the members, other than the head slider, pivoting about the vertical pivot axis being in the positive region and a clearance between the disk surface and the head slider being an allowable maximum moving amount, and the moving amount is δ2+ upon the gravity center position δ being in the negative region,
• wherein a moving amount of the head slider upon receiving the allowable maximum impact acceleration along a direction perpendicular with respect to the disk for pivoting the head support arm to move away from the disk is δ2− upon the gravity center position δ of the members, other than the head slider, pivoting about the vertical pivot axis being in the negative region and the clearance between the disk surface and the head slider being the allowable maximum moving amount, and the moving amount is δ1− upon the gravity center position δ being in the positive region, and
• wherein assuming that a smaller one between δ1+ and δ1− is δ1, and a greater one between δ2+ and δ2− is δ2, a total mass of the members, other than the head slider, pivoting about the vertical pivot axis is “m”, a mass of the head slider is “m3”, a longitudinal distance along the head support arm from the vertical pivot axis to a center of the head slider is “l2”, then gravity center position “ε” of the members, including the head slider pivoting about the vertical pivot axis is in a region satisfying equation (2) with respect to the vertical pivot axis.
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